U.S. patent number 4,781,782 [Application Number 07/034,759] was granted by the patent office on 1988-11-01 for web applicator.
This patent grant is currently assigned to Minnesota Mining and Manufacturing Company. Invention is credited to Donald J. Geisel, Robert A. Luhman, Richard J. Pilarski, Rudolf I. Shvartsman, Kent S. Tarbutton.
United States Patent |
4,781,782 |
Luhman , et al. |
November 1, 1988 |
**Please see images for:
( Certificate of Correction ) ** |
Web applicator
Abstract
A taping head for applying a film of pressure sensitive adhesive
to a receptor surface has a drive means for driving the adhesive to
the applicating roller by driving a liner supporting the adhesive,
and a dancing roll positioned between the apparatus for stripping
the liner from the adhesive and the applicating roller adjusts the
speed of movement of the film of adhesive to match the same with
the application of the adhesive. The applicator is pressed against
the receptor surface under the control of a compression device and
a cutting device for adhesive severs the adhesive below the
applicating roller and an air nozzle maintains the cut end of the
adhesive in a position for subsequent application.
Inventors: |
Luhman; Robert A. (Deer Park,
WI), Tarbutton; Kent S. (Lake Elmo, MN), Shvartsman;
Rudolf I. (Ballston Lake, NY), Geisel; Donald J.
(Clifton Park, NY), Pilarski; Richard J. (Saratoga, NY) |
Assignee: |
Minnesota Mining and Manufacturing
Company (St. Paul, MN)
|
Family
ID: |
21878418 |
Appl.
No.: |
07/034,759 |
Filed: |
April 6, 1987 |
Current U.S.
Class: |
156/361; 156/363;
156/527; 156/574; 156/523; 156/577 |
Current CPC
Class: |
B65H
35/0013 (20130101); B65H 37/002 (20130101); Y10T
156/1365 (20150115); Y10T 156/1348 (20150115); Y10T
156/1795 (20150115); Y10T 156/1788 (20150115) |
Current International
Class: |
B65H
37/00 (20060101); B65H 016/00 (); B65H
077/00 () |
Field of
Search: |
;156/361,363,523,527,574,577,362,494 ;226/44 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
Primary Examiner: Ball; Michael W.
Assistant Examiner: Aftergut; Jeff H.
Attorney, Agent or Firm: Sell; Donald M. Barnes; John C.
Claims
We claim:
1. A web applicator for applying to a surface a length of web
material carried releasably on a liner, said applicator
comprising:
a frame,
guide means directing a supply of web material to the frame,
a stripping plate supported on said frame and having an edge about
which the liner of a said web material is drawn to separate the
liner from the web,
drive means for driving said liner including a drive roller having
positive engagement only with said
an applicator roller supported on said frame in spaced relationship
to said edge,
a dancing roller disposed between said edge and said applicating
roller and positioned transversely to and engageable only with said
web,
means for positioning said dancing roller to define the normal path
of said web, and
means responsive to movement of said dancing roller for controlling
the rate of rotation of said drive roller.
2. An applicator according to claim 1 wherein said positioning
means for said dancing roller comprises a spring and an air
cylinder is provided to move said dancing roller to a set position
by applying a force to change the position of the dancing roller
against the bias of said spring.
3. An applicator according to claim 2 wherein said means responsive
to movement of said dancing roller for controlling said drive
roller comprises a linear transducer having the armature movable in
response to movement of the position of the axis of the dancing
roller.
4. An applicator according to claim 3 wherein said drive means for
said liner includes a servo motor responsive to changes in position
of said armature to said transducer for varying the speed of said
drive roller.
5. An applicator according to claim 1 wherein said applicating
roller is supported on a subframe which is spring mounted to said
frame.
6. An applicator according to claim 5 wherein means are provided
for forcing said subframe in a direction toward a receptor surface
to maintain a predetermined amount of force between said
applicating roller and said receptor surface for uniformly applying
a said web to a said receptor surface.
7. An applicator according to claim 1 wherein said frame includes a
bracket at the upper edge thereof to secure said applicator to an
automatically controlled mechanism affording a raising and lowering
or rotation of said applicator for substantially universal
positioning of said applicating roller.
8. An applicator according to claim 6 wherein said subframe is
supported from two parallel flat spring members in spaced
relationship to afford a parallelogram support for said applicating
roller.
9. An applicator according to claim 8 wherein said means for
forcing said subframe toward a receptor surface comprises a linear
acting air cylinder for applying unidirectional pressure against
said subframe to bias the same against said flat spring members
toward the receptor surface.
10. An applicator according to claim 1 wherein said applicator
includes cutting means for severing a said web between a receptor
surface and said applicating roller.
11. An applicator according to claim 10 wherein said cutting means
comprises a knife and anvil between which said web is severed.
12. An applicator according to claim 11 wherein said knife and
anvil are mounted on oscillating arms driven by a double acting air
cylinder.
13. An applicator according to claim 10 wherein means are provided
for retaining the severed end of the web adjacent the applicating
roller after operation of said cutting means.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to applicators for applying lengths of web
material to a surface.
2. Description of the Prior Art
The prior art web applicators for applying a length of web material
to a surface, such as tape heads where the web was coated with a
pressure sensitive adhesive, the receptor was either driven past
the applicating head and the web was applied to the receptor
surface or the head was moved and the article remained stationary,
and such relative movement of the head and surface dispensed the
web onto the surface. Cutting means were provided for cutting the
web at a predetermined time interval or upon a predetermined length
of tape being dispensed.
Other tape applicators include applicators for applying pressure
sensitive adhesive labels to a product. These applicating heads are
stationary. As the product to be labeled moved by, a drive means
moved a liner around a stripping edge to separate the liner from
the pressure sensitive adhesive coated label. The separated label
was then applied to the surface of the article as the same moved
past the label applicating head.
Differing from these prior art devices, the device of the present
invention provides a drive means for an adhesive web which is
separated from a liner and applied by an applicating roller to a
stationary surface as the head is moved about the surface by an
automatically controlled mechanism such as a robotic arm which is
attached to the frame of the applicating head in a manner that it
will permit the head to position the applicating roller on the
surface and rotate on the automatially controlled mechanism as a
portion of that mechanism on which the applicating head is mounted
moves along X, Y and Z coordinates to manipulate the position,
height and speed of the applicating head.
SUMMARY OF THE INVENTION
The present invention provides an applicator adapted for use with
an automatically controlled mechanism such as a robotically driven
arm for applying a length of a web to a surface. The web may
comprise a film of pressure sensitive adhesive on a liner. A
stripping plate is supported on a frame for the applicator and has
an edge about which the liner is drawn to separate the liner from
the web and a drive for driving the liner including a drive roller
having positive engagement with the liner. The liner draws the web
material off the liner to the applicating roller. The applicating
roller is freely rotatable in one direction.
A dancing roller is disposed between the separating edge and the
applicating roller and is engageable with said web. A spring member
connected to the dancing roller positions said dancing roller and
the dancing roller is also connected to means responsive to
movement of said dancing roller for controlling the operation of
the liner drive. The applicating roller is pressed toward the
product surface with a controlled pressure from an air cylinder
against the bias of two leaf springs.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention will be described in greater detail with
reference to the accompanying drawing wherein:
FIG. 1 is a schematic view of the tape applicating head of the
present invention applying lengths of tape to the surface of a
stationary article;
FIG. 2 is a side elevational view of the applicating head of the
present invention;
FIG. 3 is a rear elevational view of the applicating head of the
present invention;
FIG. 4 is a vertical sectional view of the applicating head of the
present invention taken along the lines 5--5 of FIG. 2;
FIG. 5 is a vertical sectional view taken along the lines 5--5 of
FIG. 2; and
FIG. 6 is an enlarged sectional view of the lower end of the
applicating head.
DETAILED DESCRIPTION
The present invention provides a web applicating head which may be
used, as illustrated, to apply a web of adhesive material such as a
film of pressure sensitive adhesive supplied on a liner to a
product, which web of adhesive is illustrated at 10 in FIG. 1 to
the surface of a stationary product 11. The present invention
provides means for applying the film of adhesive or other material
to a surface at essentially zero tension. Thus the film is applied
at the speed of movement of the head. This permits the adhesive to
be applied to a surface that may have a film of lubricant on the
surface and the film will remain where it is placed. The applicator
can be used for a web of pressure sensitive adhesive in
applications where a bead of adhesive or sealant was previously
used.
The applicating head is located on a portion of an automatically
controlled mechanism such as a robotically controlled arm which
portion has movement on the X, Y and Z axis such that it can
receive instruction on the Z axis to determine the height of the
head with respect to the surface and on the X and Y axis to
determine its position or its rate of movement in any direction
with respect to the Z axis, and universal movement for positioning
the applicating roller at varying angles to maintain contact with a
product surface. The illustrated taping application is provided
using a web of pressure sensitive adhesive or a tape with pressure
sensitive adhesive on either side or both sides of a backing. In
either event, the web is provided on a liner and the liner is
separated from the pressure sensitive adhesive. The adhesive is
supplied on the liner in a convolutely wound roll for use in this
application. The roll of tape material 13 may be supported on the
frame of the applicating head or remotely stored and directed along
a guide member to the head.
At the applicating head the tape web 13 is guided along a plate to
an edge 15 for separating the liner 14 from the adhesive 10 of web
13. The adhesive is then directed around a dancing roller 16 to an
applicating roller 20 which presses one surface of the adhesive
into contact with the surface of the stationary member 11.
Referring now to the other figures where the head is disclosed in
greater detail, but like parts are referred to by the same number
throughout the several views, the applicating head is provided with
a frame 21 having a bracket 22 attached thereto at the upper edge
of the frame 21 to secure the head to the portion of the
automatically controlled mechanism.
As illustrated, the frame 21 includes a transverse bar 24.
Depending from one end of the bar 24 is a bracket 25 which supports
a spool 26 which will support a supply roll 27 of the web material.
Positioned at the opposite end of the bar 24 is another bracket bar
29 from which is supported a spindle 30 for supporting a take-up
reel 31. Between the bracket 25 and the bracket 29 is a frame
member 33 which supports a liner drive mechanism 34, a liner
stripping mechanism 35, a web sensing and speed control system
generally designated 36, a cutting mechanism 38 and applicating
roller 20.
Referring first to the drive mechanism, the web is removed from the
supply spool 26 and is directed around a first idler 40 from which
the web is directed to the liner separating or striping mechanism
35. This mechanism 35 includes a plate 42 having two edge guide
plates and an edge 15 about which the liner 14 is directed to
separate the same from the pressure sensitive adhesive 10. The
liner 14 goes around the edge 15 and along the opposite side of the
plate 42 between said opposite side and a deflector plate 43. The
deflector plate 43 provides only a thin gap between it and plate 42
to restrict the adhesive 10 from following the liner 14. The liner
14 moves from between the deflector plate 43 and plate 42 to the
liner drive mechanism 34. The liner drive 34 comprises a drive
roller 44 which is supported on the frame 33. On either side of the
drive roller 44 is a pressure roller 45 which pressure rollers 45
are supported in yokes 47 which are pivoted about axes 48 to move
the pressure rollers into firm contact with diametrically opposite
surfaces of the drive roller 44. This firm contact is maintained by
a pair of springs 51 which are disposed on either side of a fixed
spring block 52 which supports the springs 51. The springs engage
the yokes for the pressure rollers 45 for urging the same about
their pivot axes 48 in a direction towards the periphery of the
drive roller 44. The drive roller 44 is driven by a servo motor 55,
as shown in FIGS. 3 and 4, to drive the drive roller 44 at varying
speeds. As the drive roller 44 is driven in the clockwise direction
as seen in FIG. 2, the liner will be drawn around the edge 15,
causing a separation of the adhesive 10 from the liner 14. From the
second of the pressure rollers 45 the liner 14 goes around a guide
roll 56 to the take-up reel 31 driven by the driven spindle 30. The
spool 26 and the spindle 30 are driven by 24 volt motors which
provide a braking action to the spool 26 and a take-up drive to the
spindle 30.
After the adhesive is separated from the liner 14, the adhesive is
directed toward the applicating roller 20. Positioned between the
separating edge 15 and the applicating roller 20 is a dancing roll
16. The dancing roll 16 is mounted on the end of a crank arm 58
joined to an axle 59 supported on the frame 33. Extending from the
opposite end of the axle 59 is a first radial arm 60 and a second
radial arm 61. The radial arm 60 extends from the axle 59 to a
position for engagement with the end 63 of a rod 64 extending from
an air cylinder 65. The cylinder 65 is actuated prior to operation
of the cutting mechanism 38 to force the end 63 against the arm 60
to rotate the axle 59 and thus the crank arm 58. The amount of
movement is sufficient to move the dancing roll 16 from its normal
position to a fixed position more nearly along a line between the
edge 15 and the applicating roller 20. When the next web
application begins the severed end of the web is positioned below
the applicating roller 20, the liner drive starts and the dancing
roll 16 is released to return to its normal operating position
under the force of a tension spring 66 connected to frame 33 and
radial arm 61.
The spring 66 then draws the adhesive 10 to the operating path and
any changes in tension on the adhesive web are reflected by
movement of the dancing roller 16 and thus movement of the second
radial arm 61 which is also connected to the end of a rod 67
extending from a linear potentiometer or voltage transducer 68. The
device 68 is referred to as a linear variable differential
transducer or LVDT and one variety Type 200 DC-D is available from
Schaevitz Engineering, Pennsauken, New Jersey. In any event,
movement of the rod 67 with respect to the transducer 68 affords
means to control the rotational speed of the liner drive servo
motor 55. The change in position of the rod 67 in the transducer 68
causes a change in the current to the drive motor 55, affording a
change in the rotation of the drive roller 44. Thus, if there is
excessive tension on the adhesive 10, the drive roller 44 will
accelerate. If the tension goes out of the adhesive 10 the drive
roller 44 will slow down. Changes in web feed speed are controlled
by the program for the robotic arm and the dancer roll 16 only
makes fine adjustments in the web tension such as when the adhesive
is applied at a corner or curve or when the applicating roller
position is moved from a horizontal path to a vertical path.
The applicating roller 20 is mounted on the head by a one way
bearing for free rotation clockwise as seen in FIG. 2. The roller
20 has an outer surface formed to avoid adhesion to the adhesive
web, e.g. knurled, silicone coated, Teflon coated, plasma coated
etc. The roller 20 is mounted on a subframe 70 which is spring
mounted with respect to the frame 33 and is movable therewith by
means of two leaf springs 71 and 72 cantilevered from a fixed
support plate 73 of a housing 74 mounted at the bottom of the frame
33. On this housing 74 is mounted a rotary double acting cylinder
75 which drives the cutting mechanism 38 for the adhesive web. The
subframe 70, which is formed like a window frame and supported on
the ends of the springs 71 and 72, is movable with respect to the
frame 33 by the springs and against the bias of the springs by a
damping device including an air cylinder 76 connected to a rocking
arm 77 pivoted about an axis 79. The rocker arm 77 has the other
end connected to a vertical rod 80 having an end member 81 which
engages a plate member 82 mounted at the top of the frame 70. The
two springs 71 and 72 of flat stock provide a parallelogram support
for the applicating roller 20. The applicating roller 20 is
supported on a shaft and journalled on a one way bearing in
cantilever fashion from a support member 83 affixed to the bottom
of the frame 70. In operation the cylinder 76 is pressurized to
apply a force against the plate 82 and force the applicating roller
20 into contact with the product surface to afford contact between
the adhesive 10 and the product surface.
Referring now to the cutting mechanism and FIGS. 2, 3, and 6, the
rotary double acting air cylinder 75 has a primary drive shaft 84
movable through an angle of 90.degree., which shaft 84 extends
through the housing 74. The end of shaft 84 is fixed to a radial
arm 85 on which a knife 86 is attached. A gear 88 is fixed to the
shaft 84, intermediate the radial arm 85 and the cylinder 75, which
gear meshes with a second gear 89 fixed on a parallel shaft 90. The
shaft 90 is supported in the housing 74 by suitable bearings. One
end of shaft 90 is attached to a radial arm 92 on the distal end of
which is an anvil member 94 cooperating with the knife 86 to sever
the adhesive 10 by the knife bursting through the web backed by the
anvil when the cylinder 75 is driven in one direction and bringing
the arm 85 and the arm 92 back to their normal rest positions when
reversed. The automatically controlled mechanism has lifted the
applicator when it is desired to sever the adhesive 10. When the
cylinder 75 is reversed, to rapidly separate the anvil and knife,
approximately one-half inch (1.27 cm) of adhesive web remains
extending below the applicating roller 20.
An air nozzle 98 is provided adjacent the periphery of the
applicating roller 20 to maintain the severed length of tape
against the surface of the applicating roller such that the web end
is positioned to engage the surface of the stationary member 11
when the automatically controlled mechanism places the applicating
head against the work surface again.
The guide roller 40, dancing roll 16 and applicating roller 20 are
all provided with an outer covering or surface to resist adhesion
of the adhesive of web 10 to such members.
Having thus disclosed the present invention with reference to a
preferred embodiment thereof, it will be appreciated that changes
can be made therein without departing from the scope of the
invention as set forth in the appended claims. For example, rather
than being mounted on an automatically controlled mechanism the
frame of the applicator may be fixed and the surface to which the
web material is to be attached may be moved, or both the frame of
the applicator and the surface to which the web material is to be
attached may be moved to provide the relative movement between the
head and the surface required for proper application of the film.
Also, the supply and take-up spools for the applicator may be
mounted on structures other than the frame of the applicator.
* * * * *